Condensed Consolidated Statements of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Premiums and other revenues:
Universal life and annuity contract charges	$ 36,199	$ 29,832
Traditional life and annuity contract premiums	4,083	4,022
Net investment income	149,558	133,515
Other revenues	5,655	9,906
Net realized investment gains (losses):
Total other-than-temporary impairment (“OTTI”) losses	(277)	0
Portion of OTTI losses recognized in other comprehensive income	78	0
Net OTTI losses recognized in earnings	(199)	0
Other net investment gains (losses)	1,366	3,092
Total net realized investment gains (losses)	1,167	3,092
Total revenues	196,662	180,367
Benefits and expenses:
Life and other policy benefits	13,678	12,216
Amortization of deferred policy acquisition costs	31,711	27,489
Universal life and annuity contract interest	101,543	92,149
Other operating expenses	20,018	20,718
Total benefits and expenses	166,950	152,572
Earnings before Federal income taxes	29,712	27,795
Federal income taxes	9,971	9,584
Net earnings	$ 19,741	$ 18,211
Common Class A [Member]
Basic Earnings Per Share:
Earnings Per Share, Basic (in dollars per share)	$ 5.58	$ 5.16
Diluted Earnings Per Share:
Earnings Per Share, Diluted (in dollars per share)	$ 5.58	$ 5.15
Common Class B [Member]
Basic Earnings Per Share:
Earnings Per Share, Basic (in dollars per share)	$ 2.79	$ 2.58
Diluted Earnings Per Share:
Earnings Per Share, Diluted (in dollars per share)	$ 2.79	$ 2.58